Being told you can't provide any value to a company, even if you improve, is soul shattering. What even was the purpose of that, apart from fostering a toxic environment? This is entirely up to the supervisor/mentor doing a poor job of supporting their juniors. They really should've hired someone more senior if that's what they were looking for. Condolences to your reader, I hope he finds somewhere that values him!
Ya it's pretty shocking that a company would have such a culture...
I have worked as CTO and some other roles that required giving reviews to people and I had to read that three times to ensure I wasn't missing something. If someday I return to being a manager and I say something like that aberration of a review I really hope that I get fired for extremely gross incompetence.
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